Manufacture of solid catalysts



I Reissue d Nov. 18,

MANUFACTURE OF SOLID CATALYSTS Charles H. Watkins, Arlington Heights,11]., assignor to Universal Oil Products Company, Des Plaiues, 111., acorporation of Delaware No Drawing. Original No. 2,748,090, dated l lay29,

1956, Serial No. 491,188, February 28, 1955. Application for reissueJuly 16, 1957, Serial No. 672,850

18 Claims. (Cl. 252-433) Matter enclosed in heavy brackets appears inthe original patent but forms no part of this reissue specification;matter printed in italics indicates the additions made by reissue.

This invention relates to the manufacture of solid catalysts which areuseful in accelerating various reactions among organic compounds, andparticularly reactions involving unsaturated organic compounds.

More particularly this invention relates to the preparation of aparticular type of an improved catalyst which is active in acceleratingdirect olefin polymerization reactions.

An object of this invention is to provide a process for preparing animproved solid [polymerization] catalyst which is utilizable inpromoting hydrocarbon conversions.

A further object of this invention is to provide an improved solidcatalyst which is useful in the polymerization of olefinic hydrocarbonsby mixing a salt of a metal of group VIII of the periodic table with anacidic oxide of phosphorus, adding said mixture to'a solid adsorbent andtreating the resultant composite with a boron halide, said catalystbeing possessed of a relatively high degree of activity.

One embodiment of this invention resides in a process for themanufacture of a solid polymerization catalyst which comprises admixinga metal salt with an acidic oxide of phosphorus, adding said mixture toa solid adsorbent, drying and calcining said composite, and treating theresultant composite with a boron halide.

A specific embodiment of the invention resides in a process for themanufacture of a solid polymerization catalyst which comprises admixingan aqueous solution of a salt of a metal of group VIII of the periodictable with phosphoric acid, adding said mixture to a solid adsorbent,drying and calcining said composite, and treating the resultantcomposite with boron trifluoride.

Another specific embodiment of the invention resides in a process forthe manufacture of a solid [polymerization] catalyst which comprisesmixing an aqueous solution of a salt of a metal of group VIII of theperiodic table with a solid adsorbent material, drying and calciningsaid composite, and treating the resulting composite with borontrifiuoride.

A more specific embodiment of the invention is found in a process forthe manufacture of a solid polymerization catalyst which comprisesadmixing an aqueous solution of nickel nitrate with phosphoricanhydride, adding said mixture to an aqueous slurry of alumina,adjusting the pH of resultant composite by means of am monium hydroxideto a value in the range of about 7 to about 10, drying and calciningsaid composite at a temperature in the range of from about 600 to about1200 F. for a period of time in the range of from about 1 to about 8hours, and treating the resultant composite with boron trifiuoride.

Other objects and embodiments of the invention will be referred to inthe following further detailed description of the invention.

The use of a solid phosphoric acid catalyst (a phosphoric acid plus asolid carrier) to polymerize propylene and higher molecular weightolefins only is known. Likewise BF supported by an inorganic oxide suchas alumina is known to polymerize propylene and higher olefins. Ametal-of group VIII of the periodic table such as nickel, compositedwith a solid carrier such as alumina has very little polymerizationactivity, while}; nickel salt of phosphoric acid on alumina polymerizesethylene primarily and the higher, molecular weight olefins to a lesserextent. j I

It has now been discovered that the activity .of solid catalyst indirect olefin conversion reactions such as the polymerization of likeolefins io'r'the copolymerization of unlike olefins (ethylene pluspropylene and higher molecular weight olefins) may be raised bypreparing the catalyst composite from the mixture of. an acidic oxide ofphosphorus, a metal salt and a solid adsorbent material, and treatingthe resultant composite with a boron halide such as boron trifluoride.v}

In the process of the present invention the starting material for thecatalytic compounds will comprise acidic oxide of phosphorus such asphosphoric pentoxide, orthopho'sphoric acid, pyrophosphoric acid,triphosphoric acid, tetraphosphoric acid; a salt of a metal of groupVIII of the periodic. table and a solid adsorbent material, the metalsalt and the acidic oxide of phosphorus being admixed before compositingwith the solid adsorbent.

In the process of this invention thesalt of the metal of group VIII ofthe periodic table suchfas nickel chloride, nickel nitrate, nickelsulfate, etc., ferric chloride,ferric nitrate, ferric sulfate, cobaltnitrate, cobalt sulfate, cobalt chloride, the aforesaid salts ofplatinum, palladium,-

ruthenium, rubidium, osmium, iridium, etc., are dissolved in water. Thepreviously decided upon acidic oxide of phosphorus in an aqueous mediumis then addedto this solution. A solid adsorbent material or carrier forthefphos phoric acid-metal salt catalyst may include inorganic metal andmetallic type oxide compositions such'as silica, alumina, zirconia,magnesia, thoria, boron oxide, etc., combinations of these oxides suchas silica-alumina, silicazirconia, silica-alumina-zirconia, silicamag'nesia, silicaalumina-magnesia, silica-thoria, alumina-boron oxide;etc.; materials of predominantly siliceous charactersu'ch asdiatomaceous earth, kieselguhr, artificially prepared porous silica,etc., naturally occurring substances such as fullers earth, clays. suchas bentonite, montmorila lonite, acid-treated clays, etc. Each adsorbentor supporting material which may be used will exert its own specificinfluence upon the net effectiveness of the composites and will notnecessarily be identical with that of other members of the class. H Anaqueous slurry is prepared by adding water to the selected adsorbentmaterial, after which the previously prepared solution of the salt ofthe metal of group VIII of the periodic table and phosphoric acid isadded there to. After a predetermined length of time, the pH of theresulting composite may, if so,desired, be adjusted to a value in therange of from about 7 to about 10, preferably in the range of fromabout8 to 9, by means of a basic compound, said compounds including thehydroxides, carbonates, acetates,'etc., of alkaline earth and alkalimetals such as calcium, barium, strontium, lithium, rubidium, sodium,potassium and magnesium. In addition to the aforementioned alkalinesubstances, ammonium hydroxide may also be used.

The composite thus formed is then-dried at elevated temperatures rangingfrom. about 200 to about 400 F. after which thecomposite is extruded bysuitable means, for example, a hydraulic press, and calcined attemperatures ranging from about 600 to about 1200 F. for a period oftime ranging from about 1 to about 8 p from approximately 75 to 100%hours to. :form a substantially solid granular catalytic material. "Thecalcination of the formed particles of catalyst is usually carried outin an atmosphere of inert gases such as air, nitrogen, line gas, and thelike.

The resultant dried and calcined composite is then treated with a boronhalide such as boron trifluoride. Boron tribromide or boron trichloridemay also be used, although not necessarily with equivalent results.

' It has also been discovered that a catalyst in which the" acidic-oxideof phosphorus is omitted may also be used to copolymerize olefins. Thiscatalyst may be prepared in essentially the same manner. as one in whichthe'acidic oxide, of phosphorus is included by admixing the salt of ametal of group VIII of the periodic table ith a solid support, dryingand calcining the resultant cmpositm'followed, by the step of treatingtheresultant mixture with boron trifluori e .e of .the ingredientsof thesolid catalysts which are manufactured by'the process of. this inventionfor use in organic reactions is.- an acidieoitide of phosphorus,preferfably one in which the, phosphorus has a valence of 5. Of thevarious acids of phosphorus, orthophosphon'c acid (H PO andpyrophosphoric acid (H P O find general application. in the primarymixtures, due mainly to the cheapness and to .the readiness with whichthey may be procured, although thefinvention is not restricted to theiruse, but, may'employ any of the other acids of phosphorus insofaras'they are adaptable. However, it is not intended to infer that. thedifferent acids of phosphorus which may be employed will producecatalysts which have identical eifects upon any given organic reactionsas each of, the catalysts produced from diiferent acids and by slightlyvarying procedures will exert its own characteristic action.

In using'orthophosphoric acid as'one of the primary ingredients,different concentrations of the aqueous solutions "may be employed, forexample, acid containing 'H PO or orthophosphoric acid containing somefreephosphorus pentoxide may be used. By this is meant that the orthoacid may contain .a definite percentage of the pyro acid correspondingtothe primary phase of dehydration of ortho phosphoric acid. Withinthese concentration ranges, the acids will be liquids ofvaryingviscosities and readily mixed with solid adsorbents.

'Triphosphori'c acids which may he represented by the formulak H P 0 mayalso be used as one of the starting materials, for the. preparation ofthe catalyst of this invention. i v A phosphoric acid mixture which isgenerally referred to as polyphosphoric 'acid may also be employed inthis process. Polyphosphoric acid is formed by heating orthophosphoricacid or pyrophospjhoric acid. .or mixtures thereor in suitable equipmentsuch as carbon lined trays heated by flue gases or other suitable meansto produce a phosphoric acid mixture generally analyzing from about 79%to about 85% by weight of P 0 Such a liquid mixture of phosphoric acidswith 79.5% P 0 content was found by analysis to contain'24.5% oforthophosphoric acid (H P0 45.2% of pyrophosphoric acid (H P O 26.0% oftriphosphor'ic acid (H P 0 ),'and 4.3% by weight of unidentifiedphosphoric acids. Another polyphosphoric acid mixture somewhat moreconcentrated than the one just. referred to and having a P 0 content of84% by weight was found by analysis to "contain about 57% by weight oftriphosphoric acid (H P O 17% by weight of hexametaphosphoric acid (HPO11% i by weight .of pyrophosphon'c acid.

(114F 0 5% by weight of 'orthophosphoric acid (H PO 'and 10% by weightofunidentified' phosphoric acids.

'Another acid of phosphorus which .may' be employed in the manufactureof a composite catalyst according to the present invention istetraphosphoric acid. It has thegeneral formula: H P O which correspondto the double oxide formula: 3H O-2P O which in turn may be consideredas the acid resulting when three molecules of water are lost by fourmolecules of orthophosphoric acid, H PO iactured by gradual orcontrolled dehydration or heating of orthophosphoric acid andpyrophosphoric acid or by adding phosphoric pentoxide to these acids inproper amounts. When the latter procedure is follow-ed, phosphoricanhydride is added gradually until it amounts to 520% by weight of totalwater present. After a considerable period of standing at ordinarytemperature, the crystals of the tetraphosphoric acid separate from theviscous liquid and it is found that these crystals melt at approximately93 F. and have a specific gravity of 1.1886 at a temperature of 60 F.However, it is unnecessary to crystallize the tetraphosphoric acidbefore employing it in the preparation of the solidcatalyst inasmuch asthe crude tetraphosphoric acid mixture may be directly incorporated withthe solid siliceous adsorbent.

In addition to the aforementioned acids of phosphorus the anhydride ofthe phosphoric acids (phosphorus pentoxide) may also be used per se,without first preparing an acid.

The resulting catalyst which has been prepared according to theaforementioned process is active for promoting the polymerization ofolefinic hydrocarbons, particularly for polymerizing like normallygaseous olefinic hydrocarbons or copolymerizing unlike normally gaseousolefinic. hydrocarbons to form normally liquid hydrocarbons suitable foruse as constituents of gasoline. When employed in the conversion ofolefinic hydrocarbons into polymers, the calcined catalyst formed ashere inbefore set forth, is preferably employed as a granular layer in aheated reactor which is generally made from steel, and through which thepreheated hydrocarbon fraction is directed. Thus, the solid catalyst ofthis process may be employed for treating mixtures of olefin-containinghydrocarbon vapors to eflect olefin polymerization, but the samecatalyst may also be used at operating conditions suitable formaintaining liquid phase operation during the polymerization of olefinichydrocarbons such as butylenes, to produce gasoline fractions. Whenemployed in the polymerization of normally gaseous olefins, the formedand calcined particles are generally placed in a vertical, cylindricaltreating tower and the olefin-containing gas mixture is passed down-Wa-rdly therethrough at a temperature of from about 350 to, about 550 F.and at a pressure of from about to about; 1500 p. s. i. These conditionsare particularly applicable when dealing with olefin-containing msterialsuch as stabilizer reflux which may contain from approximately 10. to50% or more of propylene and butylenes. When operating on a mixturecomprising essentially'butanes and butylenes, this catalyst is effectiveat conditions favoring the maximum utilization of both normal bntylenesand isobutylenes which involves mixed polymerization at temperaturesfrom about 250 to about 325 F. and a pressure of from about 500 to about1500 p. s. i.

In utilizing the catalyst of this invention for promoting miscellaneousorganic reactions, the catalysts will be employed in essentially thesame Way as they are used when polymerizing olefins in that thereactions are essentially in the vapor phase, and that they also may beemployed in suspension in liquid phase in various types of equipment.

With suitable modifications in the details of operation, the. presenttype of catalyst may be employed in a large number of organic reactionsincluding polymerization of olefins as already mentioned. Typical casesof reactions in which the present type of catalyst may be used includethe alkylation of cyclic compounds with olefins, the cyclic compoundsincluding aromatics, polycyclic compounds, naphthenes and phenols;condensation reactions such as those occurring between ethers and arc-The tetraphosphoric acid may be manutime maticsfalcohols and aromatics,phenols and aldehydes, etc.; reactions involving the, hydrohalog'enationof unsaturated organic compounds, lisomerization reactions; esterformation by the interaction of carboxylic acids and olefins; and thelike. The specific procedures for utilizing the present type of catalystin-miscellaneous organic reactions will be determined by the chemicaland physical characteristics and the phase of the reaction constituents.v

The present invention is further illustrated with respect to specificembodiments thereof in the following exs mples, which however, are notintended to limit the generally broad scope of the present invention'instrict accordance therewith.

EXAMPLE I A catalyst for the polymerization of olefinic hydrocarbons wasprepared by slurrying 300 g. of alumina gel in 150 cc. of water. 34.2 g.of nickel nitrate hexahydrate in 65 cc. of water was added to theslurry. This composite was mixed for a period of approximately 2 hours,dried at a temperature of approximately 240 F. for 16 hours, formed intog" pills and calcined at 1200 F. for 1 hour. The composite was thenreduced with hydrogen at a temperature of. about 475 F. at 500 p. s. i.g. This composite was then treated with 15 g. of boron trifiuoride, allof the boron trifiuoride being adsorbed.

EXAMPLE II Another catalyst for the polymerization of olefinichydrocarbons was prepared by slurrying 1200 g. of alumina gel and 600cc. of water. 92 g. of nickel nitrate hexahydrate and 15 g. ofphosphorus pentoxide in 100 cc. of water were added to the slurry. Thecomposite was mixed for a period of approximately 2 hours and adjustedto a pH of 2.5 by the addition of concentrated ammonium hydroxide. Thecomposite was dried, then extruded and formed into vs" pills. The driedpills were calcined at 1000 F. for a period of 3 hours in a rnufflefurnace. Boron trifluoride was passed over the composite at 325 F. untilsaturated.

Determination of activity The catalysts prepared in the previous twoexamples were tested to determine the activity thereof by processing a1:1 molar ethylene-propylene mixture over these catalysts in a jacketedreactor under conditions noted, results of said tests being set forth inTable I below:

I claim as my invention:

1. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing a metal salt with an acidic oxide ofphosphorus, adding said mixture to a solid adsorbent, drying andcalcining said composite, and thereafter treating the resultantcomposite with a boron halide.

2. A process for the maufacture of a solid [polymerization] catalystwhich comprises admixing a metal salt with an acidic oxide ofphosphorus, adding said mixture to a solid adsorbent, drying andcalcining said composite, and thereafter treating the resultantcomposite with a boron trifluoride.

3. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aqueous solution of a salt of a metal ofgroup VIII of the periodic table with an acidic oxide of phosphorus,adding :said mixture to a solid adsorbent, drying and calcining 6 saidcomposite, and thereafter treating the resultant com posite with borontrifluoride.

4. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aque-- ous solution of a salt of a metal ofgroup VIII of the periodic table with phosphoric acid, adding saidmixture to a solid adsorbent, drying and calcining said composite, andthereafter treating the resultant composite with boron trifluoride.

5. A process for the manufacture of a solid [poly* merization] catalystwhich comprises admixing an aqueous solution of a saltof a'metal ofgroup VIII of the periodic table with phosphoric anhydride, adding saidmixture to a solid adsorbent, drying and calcining said composite, andthereafter treating the resultant composite with boron trifluoride.

6. A process for the manufacture of a solid [polymerization] catalystwhich comprises mixing an aque/ ous solution of a salt of a metal ofgroup VIII of the periodic table with a solid adsorbent material, dryingand calcining said composite, and thereafter treating the resultingcomposite with boron trifluoride.

7. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aqueous solution of a nickel salt withphosphoric anhydride, adding said mixture to a solid adsorbent, dryingand calcining said composite, and thereafter treating the resultantcomposite with boron trifluoride.

8. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aqueous solution of a nickel nitrate withphosphoric anhydride, adding said mixture to a solid adsorbent, dryingand calcining said composite, and thereafter treating the resultantcomposite with boron trifluoride.

9. A process for the manufacture of a solid [polymerization} catalystwhich comprises mixing an aqueous solution of nickel salt with aphosphoric acid, adding said mixture to a solid adsorbent, drying andcalcining said composite, and thereafter treating the resultantcomposite with boron trifluoride.

10. A process for the manufacture of a solid [polymerization] catalystwhich comprises mixing aqueous slurries of silica and alumina, addingsaid mixture to an aqueous solution of a nickel salt, drying andcalcining said composite, and thereafter treating the resultantcomposite with boron trifluoride.

11. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aqueous solution of nickel nitrate withphosphoric anhydride, adding said mixture to an aqueous slurry ofalumina, adjusting the pH of the resultant composite to a value in therange of from about 7 to about 10, drying and calcining said composite,and thereafter treating said composite with boron trifluoride.

12. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aqueous solution of nickel nitrate withphosphoric anhydride, adding said mixture to an aqueous slurry ofalumina, adjusting the pH of the resultant composite by means ofammonium hydroxide to a value in the range of from about 7 to about 10,drying and calcining said composite, and thereafter treating saidcomposite with boron trifluoride.

13. A process for the manufacture of a solid [polymerization] catalystwhich comprises admixing an aque- .14. A solid catalyst comprising ametal of group VIII of the periodic table, a solid adsorbent andborontrifluoride, prepared according to the method set forth in claim 6.i

' 15. A solid catalyst comprising platinum, a solid adsorbent and borontrifluoria'e prepared according to the process set forth inclaim 6wherein said metal is platinum.

16. A solid catalyst comprising platinum, alumina, and boron trifluorideprepared according to the'processset fort/1 in. claim 6 wherein saidmetal is platinum and said adsorbent material comprises alumina.

17. A solid catalyst comprising, palladium, alumina, and borontrifluoride prepared according to the process set forth in claim 6wherein said metal is palladium and said adsorbent material comprisesalumi f '18. The process of claim 6 further Characterized in that saidmetal isplatinum.

References Cited in the file of this patent -or the original patentUNITED STATES PATENTS

